Adjustable back rest



Dec. 13, 1949 L. E. BLAZEY ADJUSTABLE BACK REST Filed Sept. 17, 1945 INVENTOR men/cs5 51 A2757 HTTORNEYJ Patented Dec. 13, 1949 uNirE-o as 2.491.154 ADJUSTABLE BACK'REST .Lawrence Blaz ey, Bay Village, Ohio,. assignor,

r by .mesne. assignments, .to .Ofiice Furniture: &

Fixtures, Inc., *of Delaware Application-September 3'Claims. 1

This invention relates ,to. .back .rests... and as by the clamping pressure. .ment of the back rest;-.with. respect to..its-angle .oftilt.

:like and "embodying-the present invention.

' companying drawing, the

L Another object of: this invention isto. provide a-back .rest.. -which is .vertically.. adjustable to different heightsand :for alllof .its 1 height adjustments remains. freely tiltable vso asto accommo- -date:itself. to the-back of the person using. the

same.

Still. another obj cot. of. ;.th e; presentv invention. is toproVide-an improved.constructiomior a back :restof..this. .character. whichis, adjustableasto height and: is Jalso. tiltable,. and wherein :the mounting means.. inclu des. alclamping means. for

holding the, back .rest at. the; desired. heightv and a pivot means which is. substantially... unafiected and permits self-adjust- A further object of the invention is. toprovide an improved constructioniof .thdcharacter mentioned, in which .thesupportfor the. back. rest has .intersectingslots which. receive a clampingv means and a pivoted mounting elemntland-wherein.

the-ability-.,-.of thebackrest to swing ortilt is substantially unaffected by the action of the clamping means.

Other objects and advantages of the invention will beapparent frond-the following 1 description when taken in conjunction with the accompanying sheet: of "drawingsfin which Fig. 1 is an elevational view, partly in section, showing a back rest applied to a chainorthe ."Fig. 2* is apartialverticalsectional view taken on line 24- 2 of Fig. 1.

Fig. 3" is a'perspective view'showing-thepom struction of the support on which the back rest is mounted, and

Fig. 4 is a perspective detail view showing the shouldered washers used in the pivotal mounting for the back rest.

Further reference will now be made to the drawing for a more detailed description of the present embodiment of the improved back rest. As mentioned above and as shown in the acback rest is well suited for use on a stenographers chair but is not limited to this particular use since it can be applied to or employed with various other forms of chairs and seats.

The improved construction of which the embodiment illustrated in the drawing represents one example, comprises in general, a back rest Washington, D; 0., acorporation 17, 1945; Seriai'No. 616,899

. I 0 .and an. upright support ,I l .uponwhich. .the

.. .back rest is mounted. 1nthisinstance;thesup- .port I iisshownasbeing asingleyertical post I .although. ,thelsupportsmay. comprise, a plurality .-.o i.postsv or..any other structuresuitable. for supporting the back rest [0. When thesupportis asingle uprightpost, as there. shown, the post is -..conneeted.to alchaiixseat or base-Knot shown) and extends ,upwa'idly at .orv adjacent .the middle .10 :ofthe rear .edge'bf-the' chair seat.

. .The. backrest 1 l 0, ,may comprise any suitable form .of backsengaging and'. supporting. member and,.as.here -shown,.ma'y be a transversely. curved wooden .member: hailing. amounting. bri'icket' i2 15 attached; thereto. J'Thetop .portionQof. the, back a rest. in may .beinthe form of arearwardly curv- .....ing. projection I [la 1,which...0verhangs .the upper 7 end of. .the. .post l L'ii'Ifhe. mounting bracket I2 preferably-includes a plate, portion 13 through 20. which. thescrews: I Lextend and a substantially flat lug or arm portion" I5 which extends rearwardly from the backrest for cooperation .with ,the post.l.l..and;has-an openingiia in the outer end thereof.

12? 'f.The.post.l.l. isherejshown as bein a wooden ,..post of. a.'substantially square .or. rectangular ..crossse'.ction and having a pairjof intersecting isslotsii and i.8..formed.therei n adjacent its upper trend. .The' slot I] extends throughthe post from withe front. to .the backthereof. andlies substanti'ally. in. the. corresponding .vertical midplane; of thepostf..Thehslotlllfl lies in the other vertical midplane of the ..post and. extends. through. the

sideto" the other and the slots .post. from .one.

1.23:, intersect each other;.for.,.substantially their full .,.length.

The back rest. In. is mounted on the post. i i .,with,the flat, lug. Ol,,S ,1Pp0Ii'/i l1g. .armi iii forming a pivoted mounting" element which extends into 4:) the slot I? and is retained therein by a clamping means 19 which includes a stem or bolt 2% extending through the slot l8 and through the opening l6 of the lug. The stem 2!) is fixed to and carried by a head or clamping member 2| 45 and has a threaded portion 22 at its other end. The stem is of a length such that when it is disposed in the slot l8 the threaded portion 22 will project beyond the opposite sides of the post. The clamping means also includes a nut so or clamping member 23 which is applied to the threaded portion 22 of the stem 20.

The back rest I0 is vertically adjustable on the post H by shifting of the stem 20 of the clamping means I 9 upwardly or downwardly to the slot 5-5 18 so as to locate the back rest at a height above the chair seat which is most satisfactory to the person using the chair. It is desirable to be able to releasably clamp the back rest at such a desired elevation and this is accomplished by tightening the member 23 of the clamping means so as to cause the abutment portions Zla and 23a of the clamping members to clampingly engage the side faces of the post II.

It is important that the back rest Ill be free to swing or tilt relative to the post II and that such swinging or tilting be substantially unaffected by the clamping pressure applied by the members 2| and 23. To this end the slot l! is made of width materially greater than the thickness of the lug l5 and means is applied to the lug to prevent the clamping pressure from gripping the same in the event that the corner portions Ila of the post are sprung inwardly by the clamping pressure applied thereto. The means for inhibiting the application of clamping pressure to the lug I5 is here shown in the form of a pair of shouldered washers 25 having plate portions 25a disposed on opposite sides of the lug and stem or shoulder portions 25b extending into the lug opening I6 from opposite sides thereof.

As shown in Fig. 2 the washers 25 are mounted on the stem 20 of the clamping means I9 and the shoulder portions 25b are of a combined length such that they hold the plate portions 25a spaced apart a distance somewhat greater than the thickness of the lug I5. In the construction just described, the lug 15 will always swing or pivot freely on the stem 25 or the shoulder portions 25b regardless of the amount of clamping pressure applied by the members 2| and 23. This will result in the back rest In being always capable of tilting freely relative to the post H so that the back rest can adjust or accommodate itself automatically to the back of the person using the chair.

From the foregoing description and the accompanying drawing, it will now be readily understood that this invention provides an improved back rest construction for stenographers chairs and usable also on various other forms of chairs and seats and wherein the back-engaging member is adapted to be adjusted as to height relative to the chair seat and to be clamped at the desired adjustment. It will also be seen that the improved construction embodies novel means permitting the back rest to tilt freely for adjustment to the back of the person using the chain and means for preventing the clamping action of the adjusting means from interfering with such desired free tilting of the back rest. Additionally it will be seen that the mounting means for the back rest is extremely simple since it embodies a minimum number of parts and there are no loose parts to become displaced or mislaid.

Although the improved back rest has been illustrated and described herein in some detail, it will be understood, of course, that the invention is intended to include all changes and modifications coming within the scope of the appended claims.

Having thus described my invention, I claim:

1. In a chair or the like, a support having a pair of intersecting slots therein, a back rest having a mounting element extending into one of said slots, clamping means extending through the other of said slots and through said mounting element and operable for applying clamping pressure to said support for holding said back rest at a desired location along said slots, said back rest being tiltable relative to said support by swinging of said mounting element on said clamping means, and means for preventing said clamping pressure from being applied to said mounting element so as to leave the latter freely swingable.

2. In combination, an upright chair post having a pair of intersecting slots extending therethrough, a back rest having a mounting lug projecting therefrom and extending into one of said slots, clamping means including a stem extending through the other of said slots and through said lug and operable for applying clamping pressure to said post for holding said back rest at a desired elevation thereon, said back rest being tiltable relative to said post by pivoting of said lug on said stem so as to be self-adjusting to the back of the person using the chair, and shouldered washer means for preventing said clamping pressure from being applied to said lug.

3. A back rest structure as defined in claim 2 in which said lug is flat and has an opening therein of larger size than said stem, said washer means comprising washers disposed on said stem at opposite sides of said lug and having shoulder portions extending into said opening of a length to prevent said clamping pressure from being applied to said lug.

LAWRENCE E. BLAZEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Murphy Oct. 17, 1944 

